Finding the Fourth Proportional to 56,141.72, 77,475.62 and 30,991.20

Step by Step Solution

1. Step 1: Write the proportion equation
   56,141.72 : 77,475.62 = 30,991.20 : x
2. Step 2: Convert to fraction form
   56,141.72/77,475.62 = 30,991.20/x
3. Step 3: Cross multiply
   56,141.72x = 77,475.62 × 30,991.20
4. Step 4: Simplify right side
   56,141.72x = 2,401,062,434.54
5. Step 5: Solve for x
   x = 2,401,062,434.54/56,141.72
6. Step 6: Final answer
   x = 42,767.88